Automatic light switch timers are traditionally wired into the mains lighting circuit.  However many of the homes in the UK do not have a neutral wire available at the switch.

So how do wire a timer which requires a neutral wire and how do they work and why do LED or energy saving lights need a neutral wire for a timer switch in the first place.

Wiring a timer switch neutral wire

For competent DIY’ers this often posed a problem as the timer switches often require a neutral wire to work.

timer switch wiring


The neutral wire is use to provide power to the light switch timer for the clock.  this does require that you have three wires at the junction box.  If you only have two wires at the switch you have a switched live type circuit.  You will need to get a neutral wire at the switch in order to correctly wire and power the device.

Most homes in the UK don’t have a neutral wire and so timer switch become quite difficult to install. However adding a neutral wire is not that easy.  An electrician should be able to add a neutral wire for you but this often requires cutting into the wall to get the wire to the switch you require it for.



So how do you install your timer with no neutral wire?

Wiring a timer

Timer wiring diagram

The simplest way is to purchase a timer that does not need a neutral wire to operate.  This way you will not need to make any changes to the switch, and the timer will work with no neutral wire.

what more the timer switches can be used energy saving bulbs also required the additional wiring of a capacitor to ensure correct operation with energy saving bulbs.

The mydome timer switch is a model which simply slides over an existing wall light switch meaning you do not need to change your switches at all.  So if you don’t understand these wiring images, we suggest you get a timer which requires no wiring.

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